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What is a porphyritic texture?

In: Geology, Laboratory Testing [Edit categories]

Answer:

A porphyritic texture is displayed in an igneous rock containing large isolated crystals (phenocrysts) in a mass of fine textured crystals . Porphyritic texture indicates that a magma has gone through a two stage cooling process. The magma has cooled sufficiently underground to allow some minerals to crystallize and grow in size; the magma is then expelled above ground where the remaining liquid magma solidifies quickly, allowing only small crystals to develop.

See link below for a picture of a porphyritic texture in a rock.

First answer by ID1129594636. Last edit by Jones1rocks. Contributor trust: 1568 [recommend contributor ]. Question popularity: 12 [Recommended].

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Relevant answers:

Describe a porphyritic texture?
A porphyritic texture is described as a rock with a fine-grained texture with a coarse-grained texture layered behind it.
How do porphyritic textures form?
Porphyritic textures are formed when magma begins to cool while it is still underground. Minerals that crystallize at higher temps will start to separate out and form crystals. As the magma cools,...
How does porphyritic texture look like?
There are 2 or more very distinct gain sizes. The smaller grains are called phenocrysts and the material around it is called matrix or groundmass. The phenocrysts are 0.3 - 5 mm. To truly see what a...
How do you determine the age of a porphyritic texture?
You cannot determine the age of a "texture". There are numerous methods for dating the age of rocks. Go to Geology.com and search for rock dating methods.
What does a rock with porphyritic texture look like?
There are 2 or more very distinct gain sizes. The smaller grains are called phenocrysts and the material around it is called matrix or groundmass. The phenocrysts are 0.3 - 5 mm. To truly see what a...